package File;

import java.io.File;

public class MkDirDemo {
    public static void main(String[] args) {
        File dir = new File("a/b/c/d/demo");
        if (dir.exists()){
            System.out.println("已经存在");
        }else {
            dir.mkdirs();
            System.out.println("已经创建");
        }
    }
}
